You need to be more specific. Mapex has, in order from high to low Orion,
Saturn Pro, Mars Pro (Pro M), Mars (M series) and Venus (V series).
Which model are you looking at?
A list of $4,800 sounds like Orion (all Maple) - which at $999 is a steal (or a dealer mistake)
Mapex does have a limited addition Pro M (6 piece) which are actually Maple shells (normally the M series are not all maple) which sells for $1,000, but this set does not include hardware (other than tom mounting). If that's what your looking at - it's still a good price for maple shells - but you would need to add on cost of hardware.
In general Mapex make good drums - the Orions a a very good top of the line set and the Saturn and Pro M serier are good semi-pro kits.